The Columbia Encyclopedia, Sixth Edition. 2001-07.
sneezeweed
name for any plant of the genus Helenium, American meadow and field herbs of the family Asteraceae (aster family), with daisylike heads of yellow (or occasionally purple) flowers. A few of the more attractive sneezeweeds are cultivated in gardens, such as varieties of H. autumnale, the most common species of E North America. The bitter sap of some sneezeweeds (e.g., H. tenuifolium, a Southern plant also called bitterweed) imparts a disagreeable flavor to the milk of cows that graze on them. Sneezeweeds are classified in the division Magnoliophyta, class Magnoliopsida, order Asterales, family Asteraceae.